The present disclosure relates generally to medical devices and, more particularly, to sensors used for sensing physiological parameters of a patient.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
In the field of medicine, doctors often desire to monitor certain physiological characteristics of their patients. Accordingly, a wide variety of devices have been developed for monitoring many such physiological characteristics. Such devices provide doctors and other healthcare personnel with the information they need to provide the best possible healthcare for their patients. As a result, such monitoring devices have become an indispensable part of modern medicine.
One technique for monitoring certain physiological characteristics of a patient is commonly referred to as pulse oximetry, and the devices built based upon pulse oximetry techniques are commonly referred to as pulse oximeters. Pulse oximetry may be used to measure various blood flow characteristics, such as the blood-oxygen saturation of hemoglobin in arterial blood, the volume of individual blood pulsations supplying the tissue, and/or the rate of blood pulsations corresponding to each heartbeat of a patient. In fact, the “pulse” in pulse oximetry refers to the time varying amount of arterial blood in the tissue during each cardiac cycle.
Pulse oximeters typically utilize a non-invasive sensor that transmits light through a patient's tissue and that photoelectrically detects the absorption and/or scattering of the transmitted light in such tissue. One or more of the above physiological characteristics may then be calculated based upon the amount of light absorbed and/or scattered. More specifically, the light passed through the tissue is typically selected to be of one or more wavelengths that may be absorbed and/or scattered by the blood in an amount correlative to the amount of the blood constituent present in the blood. The amount of light absorbed and/or scattered may then be used to estimate the amount of blood constituent in the tissue using various algorithms. This determination may be performed in a monitor coupled to the sensor that receives the necessary data for the blood constituent calculation.
Some sensors may be capable of application to multiple placement sites on a patient's body. For example, sensors may be placed on a patient's forehead, a patient's digit, etc. To determine the amount of constituent based on the sensor data, the monitor coupled to the sensor may use specific algorithms or calibration coefficients for each placement site and sensor configuration. However, the monitor should recognize (have) the correct site on which the sensor is being placed to properly calculate physiological characteristics of the patient. Accordingly, if the user of the sensor incorrectly notifies (or does not notify) the monitor of the configuration of the sensor, incorrect data may be obtained when physiological measurements are made by the pulse oximeter.